condition mean min max ZT0-3 12.4120923845 9.459814514 15.364370255 ZT4-7 20.061970025 19.139154535 20.984785515 ZT8-11 18.623597895 18.592211085 18.654984705 ZT12-15 14.99192468 14.17921552 15.804633840000001 ZT16-19 16.116408290000003 14.713986335000001 17.518830245 ZT20-23 20.84410871 20.56338735 21.12483007